Fret Calculator

This tool quickly calculates the required positions of your frets. All you have to do is enter your scale length** and the number of frets. 
Choose the unit of measurement and input your scale length and number of frets. You can switch the outcome from mm to inches or the other way around so you don't have to convert them.

**The length of your scale is the distance between your nut, measured from the side against your fretboard, and your bridge, measured from the place where the string hits the saddle. Common scales are:

Gibson: varies from 62.38, 62.55 & 62.87 cm and 64.26 cm for a long scale
Fender strat & tele: 64.77cm
Fender Jaguar: 60.96 cm
Fender Mustang & Duosonic: 57.15 cm
Martin standard: 64.36 cm
Martin short scale: 63,09 cm
PRS: 63.5 cm
Classical guitar short scale: 65 cm
Classical guitar long scale: 66 cm
Frequently used for basses is the Fender scale:
Long scale: 86.36 cm
Short scale 76.2 cm

When you're placing your bridge at a later stage and if you have movable saddles, it makes sense to position your bridge in such a way that your scale length is right in the middle of the outer sides to which your saddles can be moved.